This sets the max thread count at 48 for out set value of 12 virtual processors. You can evaluate the speedup by comparing the completion times of a job running in serial job and a job running in parallel ​with the change above.

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This changes ​the maximum ​thread count to 12 as we don't want to run more threads on a node than their are cores on that node, because ​with hyper-threading turned off any more would kill efficiency.